Dating techniques in archaeology wiki

The relationship between iron and burning means that magnetic susceptibility is often used for: Phosphate in man-made soils derives from people, their animals, rubbish and bones.

100 people excrete about 62 kg of phosphate annually, with about the same from their rubbish. A human body contains about 650g of PO4,(500g-80% in the skeleton), which results in elevated levels in burial sites.

Column sampling is a technique of collecting samples from a section for analyzing and detecting the buried processes down the profile of the section.

Narrow metal tins are hammered into the section in a series to collect the complete profile for study.

Magnetic forms of iron can be formed by burning and microbial activity such as occurs in top soils and some anaerobic deposits.

Magnetic iron compounds can also be found in igneous and metamorphic rocks.

Whatever the method of getting the phosphorus from the soil into solution, the method of detecting it is usually the same.

This uses the ‘molybdate blue’ reaction, where the depth of the colour is proportional to phosphorus concentration.

Trace element geochemistry is the study of the abundances of elements in geological materials that do not occur in a large quantity in these materials.

Because these trace elements' concentrations are determined by a large number of particular situations under which a certain geological material is formed, they are usually unique between two locations which contain the same type of rock or other geological material.

The magnetic susceptibility of a material is a measure of its ability to become magnetised by an external magnetic field (Dearing, 1999).